Lazily compute NBT

Author: octylFractal

worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/BukkitPlayer.java

@@ -39,6 +39,7 @@
 import com.sk89q.worldedit.util.formatting.text.adapter.bukkit.TextAdapter;
 import com.sk89q.worldedit.util.formatting.text.event.ClickEvent;
 import com.sk89q.worldedit.util.formatting.text.format.TextColor;
+import com.sk89q.worldedit.util.nbt.CompoundBinaryTag;
 import com.sk89q.worldedit.world.World;
 import com.sk89q.worldedit.world.block.BaseBlock;
 import com.sk89q.worldedit.world.block.BlockStateHolder;
@@ -295,11 +296,12 @@ public <B extends BlockStateHolder<B>> void sendFakeBlock(BlockVector3 pos, B bl
             player.sendBlockChange(loc, player.getWorld().getBlockAt(loc).getBlockData());
         } else {
             player.sendBlockChange(loc, BukkitAdapter.adapt(block));
-            if (block instanceof BaseBlock && ((BaseBlock) block).hasNbt()) {
-                BukkitImplAdapter adapter = WorldEditPlugin.getInstance().getBukkitImplAdapter();
-                if (adapter != null) {
-                    if (block.getBlockType() == BlockTypes.STRUCTURE_BLOCK) {
-                        adapter.sendFakeNBT(player, pos, ((BaseBlock) block).getNbt());
+            BukkitImplAdapter adapter = WorldEditPlugin.getInstance().getBukkitImplAdapter();
+            if (adapter != null) {
+                if (block.getBlockType() == BlockTypes.STRUCTURE_BLOCK && block instanceof BaseBlock) {
+                    CompoundBinaryTag nbt = ((BaseBlock) block).getNbt();
+                    if (nbt != null) {
+                        adapter.sendFakeNBT(player, pos, nbt);
                         adapter.sendFakeOP(player);
                     }
                 }

worldedit-core/src/main/java/com/sk89q/worldedit/LocalSession.java

@@ -48,6 +48,7 @@
 import com.sk89q.worldedit.session.request.Request;
 import com.sk89q.worldedit.util.Countable;
 import com.sk89q.worldedit.util.SideEffectSet;
+import com.sk89q.worldedit.util.concurrency.LazyReference;
 import com.sk89q.worldedit.util.formatting.text.TranslatableComponent;
 import com.sk89q.worldedit.util.nbt.CompoundBinaryTag;
 import com.sk89q.worldedit.world.World;
@@ -802,14 +803,16 @@ public void updateServerCUI(Actor actor) {
         }
 
         BaseBlock block = ServerCUIHandler.createStructureBlock(player);
-        if (block != null && block.hasNbt()) {
-            // If it's null, we don't need to do anything. The old was already removed.
-            CompoundBinaryTag tags = block.getNbt();
+        if (block != null) {
+            CompoundBinaryTag tags = Objects.requireNonNull(
+                block.getNbt(), "createStructureBlock should return nbt"
+            );
             BlockVector3 tempCuiTemporaryBlock = BlockVector3.at(
                 tags.getInt("x"),
                 tags.getInt("y"),
                 tags.getInt("z")
             );
+            // If it's null, we don't need to do anything. The old was already removed.
             if (cuiTemporaryBlock != null && !tempCuiTemporaryBlock.equals(cuiTemporaryBlock)) {
                 // Update the existing block if it's the same location
                 player.sendFakeBlock(cuiTemporaryBlock, null);

worldedit-core/src/main/java/com/sk89q/worldedit/blocks/BaseItem.java

@@ -21,6 +21,7 @@
 
 import com.sk89q.jnbt.CompoundTag;
 import com.sk89q.worldedit.WorldEdit;
+import com.sk89q.worldedit.util.concurrency.LazyReference;
 import com.sk89q.worldedit.util.nbt.CompoundBinaryTag;
 import com.sk89q.worldedit.util.nbt.TagStringIO;
 import com.sk89q.worldedit.world.NbtValued;
@@ -41,7 +42,7 @@ public class BaseItem implements NbtValued {
 
     private ItemType itemType;
     @Nullable
-    private CompoundBinaryTag nbtData;
+    private LazyReference<CompoundBinaryTag> nbtData;
 
     /**
      * Construct the object.
@@ -61,7 +62,7 @@ public BaseItem(ItemType itemType) {
      */
     @Deprecated
     public BaseItem(ItemType itemType, @Nullable CompoundTag nbtData) {
-        this(itemType, nbtData == null ? null : nbtData.asBinaryTag());
+        this(itemType, nbtData == null ? null : LazyReference.from(nbtData::asBinaryTag));
     }
 
     /**
@@ -70,7 +71,7 @@ public BaseItem(ItemType itemType, @Nullable CompoundTag nbtData) {
      * @param itemType Type of the item
      * @param tag NBT Compound tag
      */
-    public BaseItem(ItemType itemType, @Nullable CompoundBinaryTag tag) {
+    public BaseItem(ItemType itemType, @Nullable LazyReference<CompoundBinaryTag> tag) {
         checkNotNull(itemType);
         this.itemType = itemType;
         this.nbtData = tag;
@@ -94,30 +95,26 @@ public void setType(ItemType itemType) {
         this.itemType = itemType;
     }
 
-    @Override
-    public boolean hasNbt() {
-        return this.nbtData != null;
-    }
-
     @Nullable
     @Override
-    public CompoundBinaryTag getNbt() {
+    public LazyReference<CompoundBinaryTag> getNbtReference() {
         return this.nbtData;
     }
 
     @Override
-    public void setNbt(@Nullable CompoundBinaryTag nbtData) {
+    public void setNbtReference(@Nullable LazyReference<CompoundBinaryTag> nbtData) {
         this.nbtData = nbtData;
     }
 
     @Override
     public String toString() {
         String nbtString = "";
-        if (hasNbt()) {
+        LazyReference<CompoundBinaryTag> nbtData = this.nbtData;
+        if (nbtData != null) {
             try {
-                nbtString = TagStringIO.get().asString(nbtData);
+                nbtString = TagStringIO.get().asString(nbtData.getValue());
             } catch (IOException e) {
-                WorldEdit.logger.error("Failed to parse NBT of Item", e);
+                WorldEdit.logger.error("Failed to serialize NBT of Item", e);
             }
         }
 

worldedit-core/src/main/java/com/sk89q/worldedit/blocks/BaseItemStack.java

@@ -22,6 +22,7 @@
 import com.sk89q.jnbt.CompoundTag;
 import com.sk89q.worldedit.WorldEdit;
 import com.sk89q.worldedit.extension.platform.Capability;
+import com.sk89q.worldedit.util.concurrency.LazyReference;
 import com.sk89q.worldedit.util.formatting.text.Component;
 import com.sk89q.worldedit.util.nbt.CompoundBinaryTag;
 import com.sk89q.worldedit.world.item.ItemType;
@@ -61,7 +62,7 @@ public BaseItemStack(ItemType itemType, int amount) {
      * @param id The item type
      * @param tag Tag value
      * @param amount amount in the stack
-     * @deprecated Use {@link #BaseItemStack(ItemType, CompoundBinaryTag, int)}
+     * @deprecated Use {@link #BaseItemStack(ItemType, LazyReference, int)}
      */
     @Deprecated
     public BaseItemStack(ItemType id, CompoundTag tag, int amount) {
@@ -76,7 +77,7 @@ public BaseItemStack(ItemType id, CompoundTag tag, int amount) {
      * @param tag Tag value
      * @param amount amount in the stack
      */
-    public BaseItemStack(ItemType id, CompoundBinaryTag tag, int amount) {
+    public BaseItemStack(ItemType id, LazyReference<CompoundBinaryTag> tag, int amount) {
         super(id, tag);
         this.amount = amount;
     }

worldedit-core/src/main/java/com/sk89q/worldedit/entity/BaseEntity.java

@@ -20,6 +20,7 @@
 package com.sk89q.worldedit.entity;
 
 import com.sk89q.jnbt.CompoundTag;
+import com.sk89q.worldedit.util.concurrency.LazyReference;
 import com.sk89q.worldedit.util.nbt.CompoundBinaryTag;
 import com.sk89q.worldedit.world.NbtValued;
 import com.sk89q.worldedit.world.entity.EntityType;
@@ -45,14 +46,14 @@ public class BaseEntity implements NbtValued {
 
     private final EntityType type;
     @Nullable
-    private CompoundBinaryTag nbtData;
+    private LazyReference<CompoundBinaryTag> nbtData;
 
     /**
      * Create a new base entity.
      *
      * @param type the entity type
      * @param nbtData NBT data
-     * @deprecated Use {@link BaseEntity#BaseEntity(EntityType, CompoundBinaryTag)}
+     * @deprecated Use {@link BaseEntity#BaseEntity(EntityType, LazyReference)}
      */
     @Deprecated
     public BaseEntity(EntityType type, CompoundTag nbtData) {
@@ -66,9 +67,9 @@ public BaseEntity(EntityType type, CompoundTag nbtData) {
      * @param type the entity type
      * @param nbtData NBT data
      */
-    public BaseEntity(EntityType type, CompoundBinaryTag nbtData) {
+    public BaseEntity(EntityType type, LazyReference<CompoundBinaryTag> nbtData) {
         this(type);
-        setNbt(nbtData);
+        setNbtReference(nbtData);
     }
 
     /**
@@ -88,22 +89,17 @@ public BaseEntity(EntityType type) {
     public BaseEntity(BaseEntity other) {
         checkNotNull(other);
         this.type = other.getType();
-        setNbt(other.getNbt());
-    }
-
-    @Override
-    public boolean hasNbt() {
-        return true;
+        setNbtReference(other.getNbtReference());
     }
 
     @Nullable
     @Override
-    public CompoundBinaryTag getNbt() {
+    public LazyReference<CompoundBinaryTag> getNbtReference() {
         return nbtData;
     }
 
     @Override
-    public void setNbt(@Nullable CompoundBinaryTag nbtData) {
+    public void setNbtReference(@Nullable LazyReference<CompoundBinaryTag> nbtData) {
         this.nbtData = nbtData;
     }
 

worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/DefaultItemParser.java

@@ -30,6 +30,7 @@
 import com.sk89q.worldedit.extension.platform.Actor;
 import com.sk89q.worldedit.internal.registry.InputParser;
 import com.sk89q.worldedit.util.HandSide;
+import com.sk89q.worldedit.util.concurrency.LazyReference;
 import com.sk89q.worldedit.util.formatting.text.TextComponent;
 import com.sk89q.worldedit.util.formatting.text.TranslatableComponent;
 import com.sk89q.worldedit.util.nbt.CompoundBinaryTag;
@@ -132,7 +133,7 @@ public BaseItem parseFromInput(String input, ParserContext context) throws Input
                 }
             }
 
-            item = new BaseItem(itemType, itemNbtData);
+            item = new BaseItem(itemType, itemNbtData == null ? null : LazyReference.computed(itemNbtData));
         }
 
         return item;

worldedit-core/src/main/java/com/sk89q/worldedit/internal/cui/ServerCUIHandler.java

@@ -28,6 +28,7 @@
 import com.sk89q.worldedit.regions.RegionSelector;
 import com.sk89q.worldedit.regions.selector.CuboidRegionSelector;
 import com.sk89q.worldedit.util.Location;
+import com.sk89q.worldedit.util.concurrency.LazyReference;
 import com.sk89q.worldedit.util.nbt.ByteBinaryTag;
 import com.sk89q.worldedit.util.nbt.CompoundBinaryTag;
 import com.sk89q.worldedit.util.nbt.IntBinaryTag;

worldedit-core/src/main/java/com/sk89q/worldedit/util/collection/Int2BaseBlockMap.java

@@ -50,7 +50,7 @@ class Int2BaseBlockMap extends AbstractInt2ObjectMap<BaseBlock> {
      * @return the internal ID, or {@link BlockStateIdAccess#invalidId()} if not useful
      */
     private static int optimizedInternalId(BaseBlock block) {
-        if (block.hasNbt()) {
+        if (block.getNbtReference() != null) {
             return BlockStateIdAccess.invalidId();
         }
         return BlockStateIdAccess.getBlockStateId(block.toImmutableState());

worldedit-core/src/main/java/com/sk89q/worldedit/util/concurrency/LazyReference.java

@@ -32,6 +32,17 @@ public static <T> LazyReference<T> from(Supplier<T> valueComputation) {
         return new LazyReference<>(valueComputation);
     }
 
+    /**
+     * Pre-computed reference, for setting a lazy reference field with a known value.
+     *
+     * @param value the value of the reference
+     * @param <T> the type of the value
+     * @return the new reference
+     */
+    public static <T> LazyReference<T> computed(T value) {
+        return new LazyReference<>(value);
+    }
+
     // Memory saving technique: hold the computation info in the same reference field that we'll
     // put the value into, so the memory possibly retained by those parts is GC'able as soon as
     // it's no longer needed.
@@ -51,6 +62,10 @@ private LazyReference(Supplier<T> valueComputation) {
         this.value = new RefInfo<>(valueComputation);
     }
 
+    private LazyReference(T value) {
+        this.value = value;
+    }
+
     // casts are safe, value is either RefInfo or T
     @SuppressWarnings("unchecked")
     public T getValue() {

worldedit-core/src/main/java/com/sk89q/worldedit/util/NbtUtils.java renamed to worldedit-core/src/main/java/com/sk89q/worldedit/util/nbt/NbtUtils.java

@@ -17,11 +17,8 @@
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
-package com.sk89q.worldedit.util;
+package com.sk89q.worldedit.util.nbt;
 
-import com.sk89q.worldedit.util.nbt.BinaryTag;
-import com.sk89q.worldedit.util.nbt.BinaryTagType;
-import com.sk89q.worldedit.util.nbt.CompoundBinaryTag;
 import com.sk89q.worldedit.world.storage.InvalidFormatException;
 
 public class NbtUtils {